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As a mechanical engineer I spent 17 years in design of mechanical systems. Always seeking the best solution given budgets and adhering to efficient design principles. Often we can combine systems by hybridization, where two technologies come together in a synergistic match. I have used hybrid technologies, using ground loops and air-air fluid coolers, with heat pumps successfully in the mechanical design and construction of a number of buildings.

While wind energy may be harvested, it is not always available. Some regions get more wind than others, and there may be governmental or civic restrictions. For renewable energy, solar may be a better option than wind, even though it is only available during the day. In either case some form of auxiliary power will be required, such as batteries, grid connection, fuel powered generator, or hydro-power.

The use of heat pumps allows for the provision of a number of heating and cooling devices which may be connected to a central circulating building loop. As heat pumps have operating temperatures generally between 40F to 90F, although it may vary depending on heat energy source, such as air, water or ground. Air temperatures may vary during the day and season. As air temperature drops, heat pumps lose efficiency. We can see this in the following figure. (1)

In the case of geothermal heat pump system design, there are some options. One method is to run a water source such as a pond, river, body of water in an open loop design, in a closed loop method using an process waste heat stream or ground coupled system. Either system is usually connected to a heat-exchanger to which is connected a second closed house loop. The house loop is controlled to either discharge or gain heat from the geothermal loop.

I am attaching a blog post (2) from 2007 where I made a comment in 2009. This blog post is still getting comments. I believe such systems can be designed and constructed and would contribute to a “Net-Zero” building systems.

I am a lawyer who has been interested in the subject of energy conservation since the seventies. Back when we had the first OPEC crisis, I thought this country would head in a direction away from the consumption of huge quantities of oil and gas. It didn’t happen. Now of course, our thirst for oil has been the primary reason for a preemptive war with no end in sight. Moreover, peak oil seems to be here. And so far nothing much seems to have changed. But the public, may at last be ready for something different.

There are some real promising things happening with new solar energy systems and with wind turbines. It is long past due. But I still keep wondering whether we are approaching this problem of solving our energy demands the right way. With both solar and wind systems all technology seems to be headed toward the creation of electricity. Electricity is definitely useful but often inefficient.

Heating and cooling costs are about 60-70 percent of home energy costs. It is far more cost effective to use heat transfer than to make heat. Water source heat pumps are 300-400 percent efficient while the best ordinary HVAC systems might be forty percent efficient. (Are they that much?) What if you could even vastly surpass the efficiency of a water source heat pump. How? By making the wind pump the water instead of an electric pump.

Why not use wind to its best advantage? Make the wind do what it has done very efficiently for hundreds of years: pump water. Make it pump water from a warm place to a cold place and make it store the heat where the heat is needed or wanted. In the winter pump the heat from under the ground into the house. In the summer pump the heat from house into the ground.

To do this, because of the wind’s variability, one would need a huge (?) thermal sink in the house to slowly release the heat transferred from underground to the heat sink or to transfer the heat from the house to the ground while the wind was not blowing.

A four part system. A wind turbine. A pump. A closed loop of pipe. An interior thermal sink.

It is fairly well known that in most climates, five or six feet below ground, the temperature is a about 55 degrees. I think it is quite possible to take advantage of the geothermal underground temperature by using a wind turbine to pump water from underground into an interior thermal sink. If a large enough volume of water could be circulated to where the interior heat sink reached 55 degrees, I think such a home’s heating and cooling costs would be drastically reduced.

If the large thermal sink could get the house temperature substantially raised in the winter and substantially cooled in the summer, very little additional energy might be required to bring it to a desirable temperature with the use of a water source heat pump. A water source heat pump would work in tandem very well by using the internal heat sink as a convenient source to operate a water source heat pump.

My idea would be to use a vertical wind turbine on the roof coupled to an Archimedes screw to pumps and circulates water through the closed loop. The vertical wind turbines seem to need less wind, have more torque, and are quieter. I also think that from an architectural point of view, they would look much more attractive, especially the ones that look like spinnerets. They also take advantage of a sloping roof which increases wind speed.

I also think the Archimedes screw would be an ideal pump. It requires no gears or lubrication and could attach by a straight shaft to the vertical wind turbine. An Archimedes screw would be very inexpensive as pumping systems go and extremely reliable as there is really nothing to break.

I have other ideas about roof design and about turbine design for greater efficiency. I also have ideas about the plumbing. What I would like to see is whether there are people out there who think this idea has commercial merit and if so, how we might go about making wind driven water pumping for geothermal transfer a success. We would need some engineering and architectural expertise and some ability to fabricate the wind turbines and pumps.

I have been looking at the latest responses and it seems to me there is some confusion about this idea.

Firstly, heat pump technology, as pointed out achieves it’s high COP’s from the phase change. It is through the leveraging of the refrigerant phase change from a fluid to the gas phase where heat energy can be obtained from low temperature heat sources. This is how geothermal heat pumps can obtain heat energy from relatively low temp sources such as the ground where nominal ambient water temp would be at 55F and deliver hot water at temps of 90F to 140F.

Alternatively heat pumps can be used in air/air, air/water, water/air and water/water configurations. These are generally stand alone devices where in a properly engineered installation do not require supplemental heat sources.

Wind energy is a separate sustainable, environmentally friendly application. In my opinion the OP’s idea of using wind energy to move water around for a heat pump application is marginal and likely too capital intensive to realize any real benefit. Also, it is just too restrictive, in my opinion.

Wind energy converted directly to electricity, or other dedicated pumping applications where electricity is not available is best (water pumping up to a reservoir in agricultural or power generation schemes for example). There also may be some merit to the idea of storing the energy as compressed air, but the amount of heat generated would not be significant, usable heat source. Try heating your home with a candle.

Electricity is used by a wide range of applications, so why not use the wind energy to best effectiveness? The operation of the compressor in the heat pump and the pumps to run the water loop(s) require electricity, so do common home appliances.

There may be some applications where the proffered idea would make sense, but not likely widely applicable for single family residences unless you have a large property and money to burn.

The BC Energy Step Code is currently being implemented in British Columbia as an answer to future energy considerations in new building construction. It achieves this claim of moving towards “Net Zero” building construction by utilizing a building envelope first approach with modeling and a performance test.

The idea is that by raising a building’s theoretical energy efficiency a building will become a net zero home. In the process, there is a requirement for a certified and licensed energy adviser to be involved in the modeling, construction and testing phases of the building. (1)

In conjunction with this approach is the claim that builders can construct these buildings being “fuel-neutral”. Using this rationale the roles of mechanical systems design, testing and commissioning are omitted in the performance considerations of the building.

However, a net-zero building must include the omitted systems as the design and operation of necessary systems. These may include the ventilation and exhaust systems, water heating, laundry, and heating systems. Also, rain-water collection for irrigation and gray water systems or other load reduction schemes may all may contribute to the energy consumption and success of a “net zero” building.

Some of these services will always be required in a municipal setting such as electrical, water and waste. Reduction strategies are advised as further increases in population will add additional loads at existing consumption rates which might overload existing supply and waste systems infrastructure such as pipes and cable.

The final answer to how a building performs will be in the overall utility bills paid by the building for its operation. This includes the electrical power, gas consumption, solid and liquid waste disposal and water supplied. Unless you live in a remote rural area where none of these services are provided by a municipality, there will always be a design component of the mechanical systems that contributes to the operation of an energy efficient home.

Over the last few months my time has been occupied with travel and work. Relocation and working in construction has consumed certain amounts of time. In the process I have continued to learn and observe my working environment from the perspective of a mechanical engineer.

I have upgraded some of my technology, investing in a smart phone for it’s utility and ease of connection. However, this newer tech is still not the best for longer term research and curation efforts, such as this blog. I am happy to report I have managed to land a longer term residence which now will provide me the needed stability and access to resources, while I can set up my work space needed for more intensive endeavours.

Now relocated in Vancouver, I have a few projects in the works, and am able to get back to focusing some of my time into my own research and development, to which, is one of the major purposes of my blogging. Next week, on September 25th there is a luncheon course presentation I plan on attending regarding upcoming changes to the BC Building Code introducing The Energy Step Code. More on this topic later after the seminar.

In California we already see the movement on towards the construction of net zero buildings, as compliance to the 2016 Building Energy Standard which applies to “new construction of, and additions and alterations to, residential and nonresidential buildings.” (1) These rules came into effect January 1st, 2017. I will be reviewing this publicly available document and provide more insight and commentary at a later time.

One measure of rating homes for energy efficiency that I have seen often referenced and may be a tool for reporting and rating homes is the HERS Index as shown in the graphic.

Image 1: HERS Index scale of residential home energy consumption.

As we can see from the scale that there is reference home, so there are calculation needed to rate a home, computer methods are available online where a houses data can be input for a curious homeowner, however qualified ratings are to be done by a qualified HERS Rating technician. These ensure by performance tests that a house meets standards in actual use and perform as claimed.

A comprehensiveHERS home energy rating

The HERS Rater will do a comprehensive HERS home energy rating on your home to assess its energy performance. The energy rating will consist of a series of diagnostic tests using specialized equipment, such as a blower door test, duct leakage tester, combustion analyzer and infrared cameras. These tests will determine:

The amount and location of air leaks in the building envelope

The amount of leakage from HVAC distribution ducts

The effectiveness of insulation inside walls and ceilings

Any existing or potential combustion safety issues

Other variables that are taken into account include:

Floors over unconditioned spaces (like garages or cellars)

Attics, foundations and crawlspaces

Windows and doors, vents and ductwork

Water heating system and thermostats

Once the tests have been completed, a computerized simulation analysis utilizing RESNET Accredited Rating Software will be used to calculate a rating score on the HERS Index. (3)

As buildings become more expensive and are asked to provide ever more services there will be a movement to make these building more efficient to operate and maintain. As we do more with less, there will be social impacts and repercussions. To some these changes may be disruptive, while enabling newer markets in energy efficiency, renewables, energy storage, micro-grids and net zero buildings, to name a few.

.Hybrid Electric Buildings are the latest in developments for packaged energy storage in buildings which offer several advantages including long-term operational cost savings. These buildings have the flexibility to combine several technologies and energy sources in with a large-scale integrated electric battery system to operate in a cost-effective manner.

San Francisco’s landmark skyscraper, One Maritime Plaza, will become the city’s first Hybrid Electric Building using Tesla Powerpack batteries. The groundbreaking technology upgrade by Advanced Microgrid Solutions (AMS) will lower costs, increase grid and building resiliency, and reduce the building’s demand for electricity from the sources that most negatively impact the environment.

Building owner Morgan Stanley Real Estate Investing hired San Francisco-based AMS to design, build, and operate the project. The 500 kilowatt/1,000 kilowatt-hour indoor battery system will provide One Maritime Plaza with the ability to store clean energy and control demand from the electric grid. The technology enables the building to shift from grid to battery power to conserve electricity in the same way a hybrid-electric car conserves gasoline. (1)

In addition to storage solutions these buildings can offer significant roof area to install solar panel modules and arrays to generate power during the day. Areas where sunshine is plentiful and electricity rates are high, solar PV and storage combinations for commercial installations are economically attractive.

For utility management, these systems are ideal in expansion of the overall grid, as more micro-grids attach to the utility infrastructure overall supply and resiliency is improved.

In recent developments AMS has partnered with retailer Wal-Mart to provide on-site and “behind the meter” energy storage solutions for no upfront costs.

On Tuesday, the San Francisco-based startup announced it is working with the retail giant to install behind-the-meter batteries at stores to balance on-site energy and provide megawatts of flexibility to utilities, starting with 40 megawatt-hours of projects at 27 Southern California locations.

Under the terms of the deal, “AMS will design, install and operate advanced energy storage systems” at the stores for no upfront cost, while providing grid services and on-site energy savings. The financing was made possible by partners such as Macquarie Capital, which pledged $200 million to the startup’s pipeline last year.

For Wal-Mart, the systems bring the ability to shave expensive peaks, smooth out imbalances in on-site generation and consumption, and help it meet a goal of powering half of its operations with renewable energy by 2025. Advanced Microgrid Solutions will manage its batteries in conjunction with building load — as well as on-site solar or other generation — to create what it calls a “hybrid electric building” able to keep its own energy costs to a minimum, while retaining flexibility for utility needs.

The utility in this case is Southern California Edison, a long-time AMS partner, which “will be able to tap into these advanced energy storage systems to reduce demand on the grid as part of SCE’s groundbreaking grid modernization project,” according to Tuesday’s statement. This references the utility’s multibillion-dollar grid modernization plan, which is now before state regulators. (2)

0620 home green Rendering of the home Chris Weissflog, who operates the renewable energy firm Ecogen Energy, is building for his family. Among other green features, its solar panels will meet most of the 3,000-square-foot homeÄôs heating and cooling needs as well as powering a greenhouse with an extended growing season. With story by Patrick Langston.

>” […] The falling price of technology may still help us out of the quandary. The CHBA is currently developing a net zero and net zero-ready labelling program for home builders and renovators. A net zero home typically uses photovoltaic panels to produce as much energy as it consumes, generally selling excess electricity to the grid. A net zero-ready home is set up for, but does not include, the photovoltaic system.

The CHBA’s Foster says that a net zero home including photovoltaic panels now costs $50,000 to $70,000 more than a conventional home. That’s 50 per cent of the cost of just five years ago, and the price of PV panels continues to drop.

With rising energy prices, the CHBA says the extra monthly mortgage costs associated with a net zero home are now comparable to the savings in energy costs, making it net zero in more ways than one. […]”<

California has set a goal for all new residential construction in the state to be ZNE by 2020 and all new commercial construction to be zero net energy by 2030. Spring Lake uses no natural gas and receives most of its power from photovoltaics.

>”The $13 million Spring Lake project in Woodland has 62 affordable apartments and townhomes for agricultural workers and their families. […]

“The community will generate at least as much energy as it consumes,” says Vanessa Guerra, a project manager with Mutual Housing California, a Sacramento-based non-profit that develops sustainable affordable housing communities.

The California Energy Commission adopted zero net energy goals in its 2007 Integrated Energy Policy Report (IEPR). It further defined what ZNE buildings are and laid out the necessary steps and renewables options for achieving the ZNE 2020 goals in the 2013 IEPR.

The project was financed by the U.S. Department of Agriculture, Citibank, Wells Fargo Bank, the California Department of Housing and Community Development and the City of Woodland.”<

>” A new study reports that coastal fog in Southern California is on the decline, especially in heavily urbanized areas.

In particular, Los Angeles saw a 63 percent decrease over the last 60 years.

You can blame the heat island effect created by city streets and buildings, said the study’s author Park Williams of Columbia University’s Lamont-Doherty Earth Observatory in New York.

Fog may be a nuisance for drivers, but according to Williams, it also plays a crucial role in hydrating many costal ecosystems.

These include mountains with coastal forests and hillsides covered in chaparral, which easily burns when conditions are too dry.

“They all receive water directly from fog and benefit from the shading of these clouds,” Williams said.

In fact, he noted that in some parts of Southern California, fog may provide plants with almost as much water as rain does. Williams says this loss of coastal fog could impact the regional environment.

Fog typically forms when the air is cool enough for clouds to condense close to ground level. This often happens at night and in the early morning.

However, Williams said this process is being upset by all the concrete in urban areas, which absorbs heat in the day and slowly releases it over night, raising temperatures.

“When you increase the temperature of the surface of the Earth, then you essentially need to go higher up into the atmosphere before [it] is cool enough to promote condensation,” Williams explained.

The end result is that as cities heat up, clouds rise and fog disappears.

Data for the study came from the detailed logs of the 24 coastal airports between Santa Barbara and San Diego.

“Of course airports have been collecting really good data on clouds because the presence of clouds and their hight in the atmosphere really affects air travel,” he said.

Many of these logs had hourly updates on cloud height, some dating back to the 1940s.

Using this information, Williams and his colleagues determined that the greatest loss of fog occurred in Ontario where there was a nearly 90% decrease over the last 60 years.

Other airports such as LAX, Burbank’s Bob Hope, Long Beach Airport and John Wayne Airport in Orange County also saw a considerable decrease in the average amount of fog.

However, less urban areas like Santa Barbara and the undeveloped the Channel Islands remained quite misty.

Williams says this trend is concerning because man-made climate change is expected to heat things up even more in the future.

Coastal fog can help cool an area down but as cities continue to bake, they will gather and emit even more heat, driving away even more fog.

“That can then feedback until the cloud layer is eaten away entirely in the daytime,” he said.

Soon, Williams hopes to explore how much water fog provides Southern California in general to see whether the continued loss of these low clouds could dry out the region even more.

His current paper appears in the journal Geophysical Research Letters.”<

The Bullitt Center in Seattle, Washington, is one of the most self-sufficient buildings on the planet. It is net zero energy and, after the water reuse system is approved by city authorities, net zero water. Net zero means that the building uses the same amount as it creates or generates – it is self-sufficient.

The Living Building Challenge requires projects to avoid as many of the chemicals and substances that are found on the Red List as possible. These substances have been recognized by government agencies, such as the US Environmental Protection Agency, the European Union Commission, and the State of California, as potentially harmful to human or animal life on Earth. Not all of the substances can be avoided, though, due to the lack of availability of materials that do not contain them.

The Bullitt Center team avoided over 360 known chemicals on this list. Some were easy to avoid, as alternatives were readily available. The team also worked with suppliers to create products that met their requirements, changing the way the products were made and making them available to others.

Most plumbing valves, even those made of brass and bronze, contain up to 7% lead. Lead free valves, with an allowable lead content of only 0.25%, were used in both the potable and non-potable water systems, including fire sprinklers.Phthalates are commonly used in PVC and other plastic products. A high-performance water barrier company performed 6 months of research to develop a product that did not contain phthalates, just for the Bullitt Center project. The new product has now replaced the original version going forward. Dioxins are a by-product of the manufacture, combustion, and disposal of products containing chlorine, most notably PVC products. Couplings for no-hub ductile iron pipe are commonly made with neoprene, which contains chlorine. The team worked with the manufacturer to special order couplings made of EPDM (ethylene propylene diene monomer) rubber. The electrician was able to find electrical wire not coated in PVC that met code standards. The fiberglass insulation in the project is held together by a plant-based polymer, not the usual one that contains formaldehyde.

Certified Wood

The Bullitt Center is a wood-framed structure. Because of its location and the importance of the timber industry in the Pacific Northwest, the project team decided this was the best choice for the project. 100% of the lumber in the building has been harvested from anForest Stewardship Council (FSC) certified source. The project was also recognized as the only commercial project to receive the Forest Stewardship Council Project Certification, in recognition of responsible forest products use throughout the building.

Local Sourcing

Perhaps the greatest story about green materials and the Bullitt Center involves the curtain wall (window) system. Due to the high performance needs of the project, only one product could be used, and it was only manufactured in Europe. A Washington company partnered with the European manufacturer to gain the knowledge to manufacture and install the system in the US. The Washington company flew their employees over to find out how to make and install the system, and a licensing agreement was reached. Now this high performance system is available in the US for future projects to use.

>” […] The Edmonton centre’s designers and builders are hoping that others can learn from the project that sustainable design doesn’t have to be costly or time consuming – so much so that they have made the contract, calculations and drawings available to anyone.

The City of Edmonton said the Mosaic Centre will be the world’s most northerly commercial building to achieve net zero status, the city’s first designated LEED platinum building, the first in Alberta to be petal certified by the Living Building Challenge and Canada’s first triple bottom line commercial building.

Once completed, the new 30,000 square foot building will include photovoltaic panels that will cover much of the roof.

It will also have LED lighting designed with a time-clock/daylight controller to meet minimum light levels and a geo-exchange system which will draw heat in winter and coolant in summer.

The 32 bore hole geothermal system reduced the size of the system by 40 kW, saving about $150,000.

It was built 25 per cent ahead of schedule and five per cent under budget.

HKA architect Vedran Skopac, who worked on the project, said it was done to prove to the industry that complex, sustainable buildings can be delivered on time, on budget and without animosity between the parties.

He said the key to this all started with using Integrated Project Delivery (IPD).

The model emphasizes collaboration at an early stage and encourages all the participants to use their talents and insights throughout the different stages for best results.

“It goes all the way down to the end of the line of the tradesmen,” Skopac said.

“We invested so much in designing the process, and training and making everyone a leader.”

Skopac said a major influence on designing the actual structure was creating collision spaces, or places where building residents would be forced to meet and interact.

Skopac also wanted to influence sustainable behavior, like making windows easy to operate and open rather than using air conditioning, and making natural light penetrate deep into the building rather than encourage residents to turn on lights. […]”<

A Cambridge start-up believes its flexible solar panelling solution could fundamentally change the landscape of solar installation in the commercial sector.

The Solar Cloth Company’s award winning flexible thin film photovoltaics (FTFP) are a few micrometres thick and can be integrated into flexible and lightweight tensile structures called building integrated photovoltaics (BIPV). In doing so, they provide an alternative to traditional photovoltaic panels that are heavy and cumbersome.